The present invention relates to an expandable grain tank for an agricultural combine harvester. In particular, the present invention relates to a grain tank with a self expandable cover/tank.
It has been known in the prior art relating to grain tanks/bins for use with agricultural combines to provide tank side wall extensions for such grain tanks which are manually raised from a lowered, storage position to an elevated or “harvest” grain-retaining position in order to increase the storage capacity of the grain tank and/or to prevent spillage of the heaped grain. Such tank wall extensions are held in the raised position by mechanical securing or fastening means. In the prior art arrangement, the tank wall extensions remained in the raised position until they were manually lowered by the operator by releasing the securing or fastening means which held the tank wall extensions in their raised vertical position.
In the prior art arrangement, when the grain tank extensions are in their raised position, they cause the grain tank with the raised extensions to have a vertical height greater than that which is practical for the transporting and storage limits of the combine. Hence, in the prior art arrangement when the grain tank is not in use and before transporting or storing the combine, the grain tank extensions should be folded down into a retracted position. However, these extensions are often heavy and awkward to open and close, due in part to such extensions having to be manually operated and offer no or little protection against weather conditions.
Accordingly, a need exists for an expandable grain tank that addresses the aforementioned problems and offers a protective cover when the grain tank is either full or empty.